微型制冷系统的熵产模型及分析

Entropy Generation Model and Analysis of Miniature Refrigeration System

介绍了微型制冷系统的研制及熵产模型,分析了随着制冷系统尺寸的减小系统中各个部件熵产率的变化情况。制冷系统尺寸减小以后,压缩机内的熵产率及系统内不可逆热传导引起的熵产率增加;而换热器内由温差引起的熵产率减小,由摩擦引起的熵产率增加。对于微型制冷系统,提高微型压缩机的加工精度及减少系统内部热漏是系统成功运转的关键。

The developing and entropy generation of miniature refrigeration system was introduced. It was described how the entropy generation changed at each component in a vapor compression refrigeration system as the system scale is decreased. The en- tropy generation rate of the micro compressor and internal heat leak increase as the system size decrease. The entropy generation rate due to flow pressure drop increase as the heat exchanger size is decreased. The entropy generation rate due to the finite temperature difference decreases as the heat exchanger size is decreased. If a miniature vapor compression refrigeration system is to be successfully operated, a great deal of efforts must be made to develop a workable micro compressor and to minimize the refrigerating output loss of the evaporator.